Material receiving, storing, and dispensing apparatus



F. L. WAITE 2,707,142 MATERIAL RECEIVING, STORING AND DISPENSING APPARATUS 3 Sheets-Sheet 1 April 26, 1955 Filed June 1. 1949 U L p /L w A m m i I I I l I ||QA| I I I l I I a w h @w lllllllllllllllll Ii 2 (3 Q. M

INVENTOR FRED L. WAITE B I \9 I, 5"

ATTORNEY April 26, 1955 F. L. WAITE MATERIAL RECEIVING. STORING AND DISPENSING APPARATUS Filed June 1. 1949 3 Sheets-Sheet 2 FIG.3

INVENTOR FRED LVIAITE ATTORNEY F. L. WAITE April 26, 1955 MATERIAL RECEIVING, STORING AND DISPENSING APPARATUS Filed June 1, 1949 3 Sheets-Sheet 5 QT my B: (F9 (g vt I A 8K @u, m 8; @2 $1 INVENTOR FRED L. WAITE B ATTORNEY United States Patent Q MATERIAL RECEEVING, STQRING, AND DISPENSING APPARATUS Fred L. Waite, Long island City, N. Y., assignor to American Machine & Foundry Company, corporation of N ew Jersey Amlication .iune 1 1949 Serial No. 96 6'32 1 9 9 9 8 Claims. (Cl. 312-71) This invention relates to material receiving, storing and dispensing apparatus of the self-leveling type wherein the top or uppermost layer of material stored in the apparatus is always maintained at a constant level regardless of whether material is added to or removed from the dispensing apparatus.

Self-leveling storing and dispensing apparatuses used heretofore have relied upon an energy-storing member, such as a spring, which expands and contracts at a uniform rate depending upon the weight of material supported on the carrier so as to maintain the top thereof at a constant level. In cases where the weight of the material stored was not uniform, or where there were unusual variations in friction between the material stored and the sidewalls of the dispenser, this type of self-levelin apparatus was not always practical.

It is therefore an object of this invention to provide a self-leveling material handling device which will maintain the top of the material stored at a constant level even though the weight of the material stored in the apparatus is not uniform. Since the operation of the present apparatus does not depend upon the weight of the material stored it has a greater range of utility than devices which rely upon energy-storing means such as springs.

Another object of this invention is to provide a selfleveling material storing and dispensing apparatus which will maintain the top of the material stored in the apparatus at a constant predetermined level at times regardless of whether friction between the stored material and the walls of the dispenser varies with the distance traveled by the material supporting carrier.

Another object of this invention is to employ a suitable detector at the material receiving and discharging area of the apparatus which will control operation of a drive so as to raise or lower the stored material a distance suflicient to maintain the uppermost unit at a constant level.

Another object is to provide a photoelectric cell device for performing the detecting function and to control the operation of the drive to thereby maintain the top of the stored material at a constant predetermined level at all times.

Other objects and features of the invention will appear as the description of the particular physical embodiment selected to illustrate the invention progresses. In the accompanying drawings, which form a part of this specification, like characters of reference have been applied to corresponding parts throughout the several views to make up the drawings.

Fig. l is a side elevation partly in section of the material receiving, storing and dispensing apparatus,

Fig. 2 is a top elevation of the material receiving, storing and dispensing apparatus wherein certain parts have been broken away to show more clearly the arrangement of the sprocket chains and gear reduction motor,

Fig. 3 is a wiring diagram showing the electrical controls for controlling the operation of the gear reduction motor and for detecting the height of the material, and

Fig. 4 is a wiring diagram showing a modified form of detecting means which can be used to detect the height of the material.

While the present invention may be readily employed with material supporting carriers that are enclosed on one or more sides, I have, for purpose of illustrating the invention, shown how it may be used with a carrier enclosed on all four sides. In the illustration employed,

2,797,142 Patented Apr. 26, 1955 the material storing and dispensing apparatus has a base 10 to which may be afiixed, if desired, conventional casters 12 to enable the unit to be readily moved from place to place.

Suitable outer side walls 14 are provided for enclosing the dispensing apparatus. A removable door 16 having a handle 18 is provided at one end of the apparatus to provide access to the principal operating elements of the apparatus. The lower end of the door 16 is held in place between the flange 20 and the frame 22. To remove the door, one merely has to raise the door 16 above the flange 20 and pull the lower end out. The upper end of the door is held in place by suitable flanges of the cover plate 56. A material supporting carrier 24 is held at each corner by suitable bolts 26 which are adjustably secured to the brackets 28 and 30. The latter are attached to a pair of endless chains 34 while brackets 28 are secured to a pair of endless chains 32.

To facilitate storing superimposed bulk material in the type of apparatus employed to illustrate the invention, the path of travel of the carrier may be surrounded by a suitable shell enclosure in a manner similar to that shown in the copending application of Christopher Bockius, S. N. 736,479, filed on March 22, 1947, now Patent No. 2,649,992, August 25, 1953. The carrier enclosure shell in such a case would consist of the front wall 36 and the side walls 38 and 40. On one end of the dispenser the outside wall 14 of the same serves as the shell wall for the carrier. Suitable slots are formed vertically in the inner shell walls as, 38 and 49 through which the brackets 23 and 39 extend to permit them to be moved up and down by the sprocket chains 32 and 34. For a more detailed description of the construction of the carrier enctosure shell of the dispenser reference may be made to the patent application S. N. 736,479

ientioned above.

Each chain of the pair of endless chains 32 is driven by means of a sprocket 42. The sprockets 42 are keyed to opposite ends of a horizontal driving shaft 44. Chains 32, to which the carrier supporting brackets 28 are attached, are trained over a pair of idler sprockets 50 loosely mounted on studs 48 each of which is suitably held by its respective side wall of the dispenser. The horizontal drive shaft 44 in its center portion is keyed to aconventional reversible gear reduction motor '72, while the two ends of said shaft are supported in suitable bearings of the frame 22.

The second pair of endless chains 34, to which are attached the carrier supporting brackets 3d, are driven by means of sprockets Each sprocket is integral with a sprocket 42, so as to form a double sprocket, 42 and 43 keyed to each end of drive shaft 44. Chains 34 are also trained over idler sprockets 51, 52 and 54. The last are freely mounted on studs 53 each of which is held by the frame 22. Sprockets 52 are freely mounted on studs 55 each of which is also suitably held by its respective side Wall of the dispenser apparatus. Each sprocket Si is integral with its respective sprocket 50 so that each pair of sprockets 50 and 51 form one double sprocket each of which is loosely mounted on a stud 48 as mentioned above. Since the chains 32 and 34 are trained over the double drive sprockets 42, 43 which are all keyed on the drive shaft 44, the chains 32 and 34 always move in unison regardless of whether the carrier is moved up or down thereby maintaining the carrier always horizontal.

The top of the apparatus is enclosed by a cover plate 56 which has a rectangular opening :73 to permit the carrier 24 to be elevated to a level even with the top of the dispensing apparatus. This also permits material to move up and down freely through this opening.

Mounted adjacent each corner of the rectangular opening 58 are uprights or posts 6a) which may have, if desired, a suitable scale 61 mounted thereon. in order to determine the absence or presence of material at the top of the dispenser suitable detectors are employed. For purposes of ilustration, in the present case conventional light sources 62 and 64 and photoelectric cells 66 and 68 are employed as the detecting means and are adjustably connected to the posts which are diagonally opposite to one another so that their spacing above the top of the carrier and also the spacing between each other may be adjusted. The light beams energizing the photoelectric cells 66 and 68 are spaced from each other a dis tance sufficient to prevent the top of the material from oscillating between the high and low beams, thereby avoiding what is sometimes referred to as hunting. It will be understood that a suitable mechanical arm could be used as a detector in lieu of a light beam if desired and that the detectors do not have to be arranged in parallel, criss cross or in any other manner which best suits the particular application in which the invention is used. As shown in Figure l, the beam of light passing from the light source 62 to the photo-electric cell 66, is positioned at a lower elevation than the beam from the light source 64 to the photo-electric cell 68.

Photocell detectors are connected through a central box 78 with the gear reduction motor 72 so that when the lower light beam is not broken after a predetermined length of time by stored material, such as the boxes 70 supported on the carrier 24, it will cause the gear reduction motor 72 to be operated to raise the carrier 24 a distance sufficient to cause the material to actuate the detector or interrupt the light beam. The upper detector or light beam, on the other hand, is so connected to the gear reduction motor 72 that when this light beam is interrupted for a predetermined length of time the gear reduction motor 72 is actuated so as to lower the carrier 24 a distance suflicient to avoid interrupting the upper light beam.

A suitable upper limit switch 74 is attached to the dispenser which prevents the lower photoelectric ceil 66 from actuating the gear reduction motor 72 when the carrier 24 has reached its uppermost limit of travel. A similar limit switch 76 is attached to the lower end of the housing to be actuated by the bracket 28 when the carrier 24 reaches its lowermost limit of travel. The photoelectric cell 68 will therefore be prevented from causing the gear reduction motor 72 from lowering the carrier 24 still further.

The electrical controls are enclosed in a conventional control box 78. Mounted on the control box 78 is a conventional automatic cord reel 80 on which the cable 82 is automatically reeled in when the electric plug 34 is detached from the power outlet.

The operation of my invention may be briefly described as follows:

When the carrier 24 is in its uppermost position the normally closed limit switch 74 is opened by the bracket 28 engaging therewith. When material 70 is placed on top of the carrier the upper light beam acting on the photocell 68 and the lower light beam acting on the photocell 66 are momentarily broken as the material passes past the light beams. Temporary interruptions of the light beam in this manner, however, do not cause the gear reduction motor to operate because conventional time delay relays 86 and 88 are interposed in the circuits connected to each of the photoelectric cells. These time delay relays do not allow electrical current to go through to the gear reduction motor unless the interruption prevails beyond a predetermined length of time.

As material is stacked on the carrier it will reach a height where it interrupts the upper light beam energizing the photocell 68 for a period suificient to allow time delay relay 86 to pass the impulse through to the relay 90. When the relay 90 is energized it will cause electrical current to flow from power lines 92 and 94 through the field winding 96 in one direction in the gear reduction motor 72 to thereby cause the carrier 24 to be lowered with the material stored thereon.

As the carrier 24 descends the bracket 28 moves out of contact with the limit switch 74 thereby allowing the switch 74 to assume its normal closed position. When the carrier 24 has moved downwardly a sufficient distance to cause the light source 64 to energize the photocell 68 the relay 90 is de-energized. Photocell 68 is of conventional construction and is of the type which causes a relay to be energized when the light beam is interrupted. Photocell 66 on the other hand, is of the conventional type which normally energizes a relay when the light beam is not interrupted.

As material is added to the apparatus the light beam energizing the photocell 68 is similarly interrupted for a length of time sufficient to allow current to pass through the time delay relay 86 thereby causing the relay 90 to be energized. This causes electrical current flowing from power lines 92 and 94 to again flow through the field winding 96 of the reversing motor 72 in the same direction, thereby causing the shaft 44 to be driven to move the sprocket chains 32 and 34 over their respective sprockets and thereby lower the carrier 24 a distance suflicient to allow the light beam energizing the photocell 68 to be restored.

If material 70 is removed from the dispensing apparatus, the lower light beam energizing the photocell 66 is not interrupted for a length of time sufficient to allow current to pass through the time delay relay 88 and energize the relay 98 through the normally closed switch 74. When the relay 98 is energized it causes electrical current to flow from the power lines 92 and 94 through the field winding 96 to the reversing motor 72 in the opposite direction. This causes the motor 72 to rotate in the opposite direction and thereby revolves the drive shaft 44 in the opposite direction. In this manner the double drive sprocket 42, 43 move sprocket chains 32 and 34 over their respective sprockets in the opposite direction thereby raising the carrier 24 a distance sufficient to interrupt the light beam which energizes the photocell 66.

When the photocell 66 is not energized it also causes the relay 98 to become de-energized thereby stopping the operation of the reversing motor 72. Since the motor 72 has a self-locking drive, such as a worm and worm gear, when the motor is not operating it maintains the carrier 24 stationary and thereby maintains the top of the material supported on the carrier at a constant level. It will thus be seen that as material is added to that already supported on the carrier 24, the carrier 24 automatically descends until the top of the material is located between the upper light beam and the lower light beam.

When sufficient material is added to that on the carrier 24 the bracket 28 descends to a point where it engages with the normally closed limit switch 76 thereby opening the same and interrupting the circuit between relay 90 and the amplifier 100 of the photoelectric cell 68. Therefore, even though additional material is added to the dispenser which causes the upper light beam energizing the photocell 68 to be interrupted, this in terruption of the light beam is incapable of causing the relay 90 to be energized because normally closed limit switch 76 is open. Therefore, the motor 72 will not be operated. Photocell 66 similarly forwards impluses through the amplifier 102.

It will thus be seen that I have provided self-leveling material storing and dispensing apparatus which always maintains the top of the material stored in the apparatus at a constant predetermined elevation even though the material supported on the carrier 24 is not of uniform weight or shape. It will also be noted that even though friction between the material stored on the carrier 24 and the inner shell of the apparatus which laterally supports the material stored on the carrier 24- varies over the length of travel of the carrier the top of the material will nevertheless be automatically brought up or down to the pre determined level desired since the motor 72 has sufiicient power to overcome any differences in friction on this account.

The modified form of my invention shown in Fig. 4 shows how a single photo-electric light beam could be used as a detector instead of the double light beam shown in the drawings previously described. In this case when the plug 104 is connected to a suitable source of current the light source 106 is actuated causing a light beam to be projected across to the photo cell 108. The detection of the light beam by the photo cell 108 actuates an amplifier 110 which causes current to flow through a suitable time delay relay 112 to energize the relay 114. The time delay relay 112 prevents the relay 114 from being actuated by an operator accidentally interrupting the beam when adding or removing material from the dispenser. When the relay 114 is energized it causes armature 116 to be pulled upwardly. If the dispenser is tobe loaded the operator puts the switch 118 on load position. This double throw single pole switch 118 is of conventional construction and is mounted on the housing of the self leveling dispenser where it is readily accessible to the operator.

When sutficient material has been placed on the material supporting carrier of the self leveling dispenser the uppermost unit will cause the light beam passing from the light source 106 to the photo cell 103 to be interrupted. After the light source has been interrupted for a sullicient length of time the relay H4 is deenergized. Current then passes through the wires 129, through the normally closed lower limit switch 122, through the contacts 124, wire 126, through fielding winding 128 of a conventional reversing motor 136, through the contact 132 to wire 134 connected with the source of current thereby causing the motor 130 to rotate in a direction which lowers the carrier a distance suflicient to bring the top of the material placed on the carrier below the light beam.

As soon as the light beam is restored the relay 114 is again energized through the amplifier 11d and the time delay relay 112. In the loading process this is repeated until a sufficient amount of material has been placed on the carrier so that it has descended to its lowermost limit, the limit switch 122 will be opened in the same manner as previously described with respect to the embodiment shown in Fig. l. The opening of switch in prevents the motor 13% from being further driven in this direction when the carrier has reached the lowermost limit of its travel.

To unload the dispenser, the operator turns the switch 113 to unload position. Current then flows through wire 126, wire me, through the upper limit switch 133, contacts 140, through field winding 128 in the opposite direction, through wire 126, through contacts 142, through wire 144 back to the source of power 134, thereby causing the reversing motor 130 to rotate in the opposite direction. This causes the carrier to ascend thereby allowing the bottom limit switch 122 to resume its normahy closed position.

When the carrier has risen a sutlicient distance the top of the material thereon will interrupt the light beam. This interruption of the light beam causes the relay 114 to be deenergized thereby stopping the motor 139. As sufficient material is removed from that stacked on the carrier the light beam is again restored and the process just described is again repeated to cause the carrier to ascend a distance sufiicient to cause the top of the material supported thereon to interrupt the light beam thereby stopping the motor 138 again.

When all material has been removed from the self leveling dispenser the carrier will reach its uppermost position and thereby cause the top limit switch 138 to be opened which prevents additional current from flowing through the wire 136 thereby preventing the motor 133 from being driven in a direction which causes the carrier to rise, even though the light beam may be broken.

it will therefore be evident that a single detector, as shown in the modified form of my invention, may be used for detecting the position of the top of the material supported on said carrier instead of a double detector device such as that previously described with respect to the embodiment shown in Fig. i. it will also be understood that various types of conventional arm actuated switches could be employed in lieu of the photo electric cell detector used to illustrate the invention. The electrical connections in such a case would be the same and the switch detector so employed would actuate the time delay relays ('26, 83 and 112. as the case might be depend ing on whether one or more detectors were used. Since such a substitution of detectors would be obvious in view of the preceding description a further disclosure in this connection has not been deemed necessary and has been omitted for the sake of brevity.

The invention above described may be varied in construction within the scope of the claims, for the particular device selected to illustrate the invention is but one of many possible embodiments of the same. The invention, therefore, is not to be restricted to the precise details of the structure shown and described.

What is claimed is:

1. Material storing and dispensing apparatus of the self-leveling type comprising a housing, a material supporting carrier suspended from flexible members and being movable relative to said housing, a photocell detector positioned at one elevation at the top of said housing, a second photocell detector positioned at a lower elevation than the first named detector, means interconnecting one of said detectors with a power drive to move said carrier upwardly until one of said detectors is actuated by the material supported on said carrier, a second means for connecting the other detector to said power drive to move said carrier in the opposite direction when said S detector is actuated by the material supported on said carrier, a time delay relay interposed in each of the means connecting said photoelectric cell detectors with said power drive to effect a delay between the time a detector is actuated and the time said power drive is operated.

2. Apparatus for receiving storing and dispensing material wherein the top of the material stored in said apparatus is automatically maintained at a constant level regardless of whether material is added to or removed from the apparatus, said apparatus comprising, a framework, a material carrier for supporting material stored in said apparatus, a housing mounted on said framework, a reversible motor mounted in said housing for moving said carrier relative to said framework and housing, a light source, a photoelectric light cell connected to said framework to detect said light source, a circuit connecting said photoelectric light cell with said reversible motor to drive said reversible motor in one direction when said light source is not detected, a second photoelectric cell connected to said framework at a point spaced below said last-named photoelectric light cell, a second circuit cpnnecting said photoelectric light cell with said reversible motor to drive said reversible motor in the opposite direction as long as said light source is detected by the second photoelectric light cell, to thereby maintain the top of the material stored on said carrier between two light beams, a time delay relay interposed in each of the circuits connecting said photoelectric light cells with said reversible motor to effect a delay between the time a photoelectric light cell is actuated and the time said motor is operated, and a limit switch interposed in each of the circuits connecting said photoelectric light cells with said reversible motor to open one of said circuits when the carrier has reached the limit it can move in any one direction to stop the reversible motor from moving the carrier further in said direction.

3. Material receiving, storing and dispensing apparatus of the type wherein the top of the material stored in said apparatus is automatically maintained at a constant level regardless of Whether material is added to or removed from the material stored in the apparatus, said apparatus comprising a framework, a housing, a material carrier, a reversible motor mounted in said housing for lowering said carrier when driven in one direction and for raising said carrier when driven in the opposite direction, a photoelectric cell mounted at the upper end of said framework for causing said reversible motor to move said carrier in one direction when said photoelectric cell is actuated and for stopping said motor from moving said carrier in said direction when light actuating said photoelectric cell is cut off, a second photoelectric cell spaced beyond said first-named photoelectric light cell for causing said reversible motor to move said carrier in the opposite direction when a light beam actuating said photoelectric cell is broken and for stopping said motor from moving said carrier in said direction when light actuating said second photoelectric cell is restored, and a time delay relay connected with each of said photoelectric cells to delay the actuation of said motor until a predetermined length of time has elapsed after either or said photoelectric cells have been actuated.

4. Material receiving, storing and dispensing apparatus of the type wherein the top of the material stored in said apparatus is automatically maintained at a constant level regardless of whether material is added to or removed from the apparatus, said apparatus comprising, a framework, a housing mounted on said framework, a carrier rier for supporting material stored in said apparatus, an electrically operated reversible motor mounted in said housing for lowering and raising said carrier and the material supported thereon, a photoelectric cell mounted at the upper end of said framework and housing, a manually operated double throw switch mounted on said framework, 21 source of electric current, an electrical circuit connecting said switch with said reversible motor to drive said motor in one direction each time current flows in said circuit, a second electrical circuit connecting said switch with said motor to drive said motor in the opposite direction each time current llows through said second circuit, and a relay controlling the flow of current through said circuits, said photoelectric cell actuating said relay when the presence or" material is detected.

5. Apparatus of the self-leveling type which comprises, a framework, a housing mounted on said framework, a carrier mounted for movement relative to said housing, a

plurality of electrical circuits, a reversible motor mounted in said housing for moving said carrier in one direction when current fiows through said motor through one of said circuits and for moving said carrier in the opposite direction when current flows through said motor through another of said circuits, a manually operated switch mounted on said housing for controlling the circuit through which electrical current will flow to said electrical motor, a detector mounted on said housing for detecting the presence of material mounted at the material receiving and dispensing end of the dispenser, and means connecting said detector with a relay to control the flow of current through either of said circuits Whenever the presence of material is detected to automatically cause the carrier to be raised or lowered to maintain the top of the material supported thereon at a constant level.

6. Apparatus of the self-leveling type which comprises, a framework, a housing mounted on said framework, a carrier mounted for movement relative to said housing, a plurality of electrical circuits, a reversible motor for moving said carrier in one direction when current flows through said motor through one of said circuits and for moving said carrier in the opposite direction when current flows through said motor through another of said circuits, a manually operated switch mounted on said housing for controlling the circuit through which electrical current will flow to said electrical motor, a detector mounted on said housing for detecting the presence of material mounted at the material receiving and dispensing end of the dispenser, means connecting said detector with a relay to control the fiow of current through either of said circuits whenever the presence of material is detected to automatically cause the carrier to be raised or lowered to maintain the top of the material supported thereon at a constant level, and a time delay relay interposed between said detector and said relay to delay the motor from being driven until the detector has been actuated for a predetermined length of time.

7. Apparatus of the self-leveling type which comprises, a framework, a housing mounted on said framework, a carrier mounted for movement relative to said housing, a plurality of electrical circuits, a reversible motor for moving said carrier in one direction when current fiows through said motor through one of said circuits and for moving said carrier in the opposite direction when current flows through said motor through another of said circuits, a manually operated switch mounted on said housing for controlling the circuit through which electrical current will flow to said electrical motor, a detector mounted on said housing for detecting the presence of material mounted at the material receiving and dispensing end of the dispenser, means connecting said detector with a relay to control the flow of current through either of said circuits whenever the presence of material is detected to automatically cause the carrier to be raised or lowered to maintain the top of the material supported thereon at a constant level, and a limit switch interposed in each of said circuits and mounted on the framework at a position where one of said switches will be opened whenever the carrier has reached the limit it is capable of travelling in any one direction.

8. Apparatus of the self-leveling type Which comprises, a framework, a housing mounted on said framework, a carrier mounted for movement relative to said housing, a plurality of electrical circuits, a reversible motor for moving said carrier in one direction when current flows through said motor through one of said circuits and for moving said carrier in the opposite direction when current flows through said motor through another of said circuits, a manually operated switch mounted on said housing for controlling the circuit through which electrical current will flow to said electrical motor, a detector mounted on said housing for detecting the presence of material mounted at the material receiving and dispensing end of the dispenser, means connecting said detector with a relay to control the flow of current through either of said circuits whenever the presence of material is detected to automatically cause the carrier to be raised or lowered to maintain the top of the material supported thereon at a constant level, a time delay relay interposed between said detector and said relay to delay the motor from being driven until the detector has been actuated for a predetermined length of time, and a limit switch interposed in each of said circuits and mounted on the framework at a position where one of said switches will be opened whenever the carrier has reached the limit it is capable of travelling in any one direction.

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